Control circuit for switching power supply
US8598800B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 19, 2011 |
| Grant date | Dec 3, 2013 |
| Priority date | — |
| Expiry date | Dec 28, 2031 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B20/30
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A soft-start circuit generates a soft-start voltage Vss having a voltage level that rises over time. A pulse width modulator generates a PWM signal having a duty ratio adjusted such that a feedback voltage Vout′ that corresponds to the output voltage Vout of the switching power supply matches the soft-start voltage Vss. A driver circuit controls a switching element according to the PWM signal. A capacitor is arranged such that one terminal thereof is set to a fixed electric potential. A current source generates a charge current that flows intermittently in synchronization with the PWM signal so as to charge the capacitor. The soft-start circuit outputs, as the soft-start voltage Vss, a voltage that occurs at the capacitor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.